Sodium pentobarbital abolishes bursting spontaneous activity of dorsal cochlear nucleus in rat brain slices

There is evidence that pentobarbital, a commonly used anesthetic, can affec t neuronal activity, but its effects on particular neurons of the dorsal co chlear nucleus (DCN) are not well known. Bursting (complex spiking) spontan eous activity has been observed in the DCN in brain slice preparations and in recordings from unanesthetized decerebrate animals, but seldom in experi ments with anesthetized animals. This study investigated the effects of pen tobarbital on spontaneous activity in the DCN in brain slices. Most extrace llularly recorded bursting neurons decreased firing rates and reversibly ch anged their firing to simple spiking with irregular intervals during pentob arbital. Some reversibly stopped firing after the change to an irregular pa ttern. Most neurons with regular spontaneous activity (simple spiking) show ed decreased firing rates and more irregular intervals during pentobarbital . The results also suggest some involvement of gamma-aminobutyric acid type A receptors in the pentobarbital effects. (C) 2000 Elsevier Science B.V. A ll rights reserved.